Looking for running '77-'79 CT70 engine.

Discussion in 'Wanted/Looking For' started by Waveraider, Mar 25, 2012.

  1. Waveraider

    Waveraider Member

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    Looking for a good running engine to fit my '79 CT70. I already have a carb and intake. I don't know much about these, but have been told pre-'77 engine won't work. Please PM or email me at jimsweeneyindy@comcast.net.
     
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  3. racerx

    racerx Administrator
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    Any Z50-based 3-speed engine, including the numerous 72cc flavors, will bolt-in directly. K1-`81 CT70 motors are all the same, except for the SN.

    You could use a K0, `82, or `91-`94. K0s have different primary gearing, so you'd need to fit a 38t sprocket at the wheel, in place of the 35t. `82 has some oddball (among CT70s) internal parts, but is virtually plug & play. `90s era lumps are 12v/CDI so you'd have some wiring work, plus battery & bulb changeouts. Any of these could work for you.
     
  4. Waveraider

    Waveraider Member

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    Racerx. I have a spare K0 engine. Are you saying everything is pretty much a plug-n-play? I was led to believe 76 and older were not compatible with 77-79.
     
  5. racerx

    racerx Administrator
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    You should be able to swap your entire, running, K0 motor & carb. K0 doesn't have a neutral switch, so 3 leads in the modular plug instead of 4. Do verify that they are positioned the same as the harness-side in your `79; color-coding is the same for all 6v motors.
     
  6. DeRider

    DeRider Member

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    Hey Waverider, I'm sorry if I've confused you with my last post on your ignition switch. The ignition switch itself is specific to the 77,78 and 79. If you're wanting to have the horn, headlight, taillight, brake and turn sig's all work then to have a plug and play you'll need these years ignition switch. 69-76 are 3 position switch's whereas 77,78 and 79 are 2 position. Soory for the confusion. Rich
     
  7. Waveraider

    Waveraider Member

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    Racerx. Thanks for the help on this. I think I'll install my K0 engne and see how it works.

    DeRider. You didn't really confuse me. I need everything working right. Just hoping I could use the '79 switch in my K3. Since then I ordered the right switch and wiring harness fot it. I was thinking about parting my '79 CT, but it's too complete and restorable than to rip apart. If I can throw my K0 engine on with no problem, life is good.

    I'm sure my explanation now hs everybody confused.
     
  8. racerx

    racerx Administrator
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    It'd be simpler to use a K3 switch in a `79 than the other way around. With the former, you'd have a useless second position. The latter would require a handlebar-mounted light control unit to switch the lights on/off. IMO, you did the right thing. Those late-`70s key switches (along with other parts) are rare as rocking horse s*** anymore.
     

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